Public Switch Telephone Network (PSTN)

2nd June 2025

Communication providers are upgrading the technology they use to provide landline and telephone services with a fully digital network. As part of this upgrade, the existing network called the Public Switched Telephone Network (PSTN) will be withdrawn.

For the majority of customers the upgrade to VoIP (Voice Over Internet Protocol) has already happened and will be completed by January 2027. The government is working together with the telecommunications industry to ensure that all customers and critical services are protected and prepared.

If someone uses a landline to make voice calls today (in 2025) then they can continue to use a landline in future. However, in some cases it may be necessary to change communication provider, if the current provider does not offer a voice service in future.

Charters and Checklist
Following work with the government, communications providers and network operators signed voluntary charters in December 2023 and March 2024, ensuring their commitment to protect vulnerable consumers during the PSTN migration.

In November 2024, major communications providers signed the PSTN Critical National Infrastructure (CNI) Charter, which sets out steps that the telecoms industry will take to protect CNI assets through the migration. Also, in November 2024 major communication providers agreed a checklist of safeguards before transferring customers from old analogue phone lines onto a digital network, reducing the risk of them being disconnected during the migration.

For more details go to
https://www.gov.uk/government/collections/public-switch-telephone-network-pstn